1. Field of the Invention
The present invention relates generally to testing of antenna arrays. More specifically, the present invention relates to a miniature test chamber for the ALR-67 Radar Warning Receiver antenna array.
2. Description of the Prior Art
The ALR-67 Radar Warning Receiver is an advanced Countermeasure Receiving Set that is the standard U.S. Navy radar warning receiver that is deployed on carrier based F/A-18 tactical aircraft. The ALR-67 Radar Warning Receiver, which includes a countermeasure computer is designed to enhance the survivability of pilots and their aircraft in a hostile environment. The ALR-67 Radar Warning Receiver also has a low band antenna array which is mounted on the aircraft fuselage in proximity to the cockpit.
There is currently a need to test the ALR-67 Low Band Antenna Array as an integral part of a total system for the ALR-67 Radar Warning Receiver. The testing needs to be performed over the frequency range of operation of the ALR-67 Low Band Antenna Array. Previous attempts to design a test chamber for the antenna array have not been acceptable in that the test chamber achieved acceptable operation over only a very small portion of ALR-67 Low Band Antenna Array's frequency range of operation.
There is a need to provide an anechoic chamber which is small in size and constructed so that electromagnetic interference does enter or exit the chamber. There is also a need to provide a test signal to the ALR-67 Low Band Antenna Array at a specific azimuthal angle. The frequency response of the antenna array should be 30 dB+/−10 dB over the frequency range of operation of the antenna array with no resonance peaks or dropouts.